Israeli snipers have killed at least 29 unarmed Palestinians protesting on the Gaza border to demand, among other things, refugees' right to return.

Citizens in the United States and United Kingdom are protesting against the killing of at least 29 Palestinians in the Great March of Return in Gaza, as the international Boycott, Divestment and Sanctions (BDS) movement renews calls for an arms embargo against Israel.

In the United States, Jewish group If Not Now has organized several actions: in New York, members walked to the 'progressive' Union for Reform Judaism to highlight its silence on the use of lethal force by Israeli forces against unarmed civilians during protests commemorating Land Dayand demanding Palestinian refugees' right to return.

During the protest, If Not Now member Rivka Mitnik-Kostanyan recited the 10 Plagues of Occupation: "Settlements and land dispossession; restriction of movement and checkpoints; curfews; imprisonment; systems of segregation; extrajudicial killings, surveillance; desecration of religions; massacres and inter-communal violence; and the killing of those standing up to oppression."

In Washington D.C., they protested Thursday outside the headquarters of prominent Israeli-lobby organization the American Israel Public Affairs Committee (AIPAC), to protest Israel's actions.

At least 2,000 protesters in London marched Saturday in solidarity with the Palestinian people after Israeli snipers killed 29 unarmed demonstrators in Gaza, calling on the government of the United Kingdom to hold Israel accountable.

Other rallies were also held in Manchester, Sheffield and Bristol.

U.K. Labor party leader Jeremy Corbyn told reporters that Palestinians have "a right to protest against their appalling conditions and the continuing blockade and occupation of Palestinian land, and in support of their right to return to their homes and their right to self-determination… Firing live ammunition into crowds of unarmed civilians is illegal and inhumane and cannot be tolerated."

Meanwhile, the BDS movement renewed calls urging the international community to impose a two-way military embargoon Israel after Israeli snipers killed at least 17 Palestinians on March 30, the first day of the ongoing March of Return.

The BDS National Committee called the actions a "massacre," comparing it with the 1960 slaughter of peaceful protesters in Sharpeville, in apartheid South Africa.

The embargo aims to end all arms transactions with Israel, and it has precedent: it was imposed on apartheid South Africa.

According to the National Committee, the embargo is necessary because "the export of Israeli military technology, 'field-tested' on Palestinians, contributes substantially to financing Israel's oppression of Palestinians."

Palestinians in Gaza have vowed to continue protests until May 15, which marks 70 years since the Nakba ('catastrophe'), when over 700,000 Palestinians were expelled or fled their towns and cities after the establishment of the state of Israel on May 14, 1948.

While Israeli top officials have asserted they will continue using lethal force against protesters near the Gaza border, the United States has blocked two attempts by members of the United Nations Security Council to launch an independent investigation into violence in Gaza.